Sequence Settings

I have fcp 6.0.5
When I bring media to the timeline it asks me what sequence settings I want....I chose the option for dvcpro 720 24p which is what the file is.....but on the timeline it makes the sequence into a dvcpro 720 60p....I try to change the settings from the timeline and it will not give me a dvc pro 720 24p option....onlu a 60p option....how can I change this?